Robbins, a politically impartial government employee, spearheaded May's negotiations on a deal with the European Union that would manage the country's departure from the bloc.

Though the sides succeeded in agreeing a Withdrawal Agreement last November, May repeatedly failed to garner enough domestic support for it to pass through Britain's parliament, and she resigned earlier this year.

Robbins, 44, has attracted criticism from prominent Brexit supporters who accused him of being too pro-EU.

But new Prime Minister Boris Johnson - who has himself said the deal would turn Britain into a "vassal state" - paid tribute to Robbins on Monday.

Robbins will first spend a sabbatical at the University of Oxford, becoming the first holder of a visiting fellowship set up in memory of former Cabinet Secretary Jeremy Heywood.

"I am delighted that Olly will be the first Permanent Secretary to take up this Fellowship in Jeremy Heywood's memory, which follows his many years of dedication to public service in a variety of different roles," Johnson said in a statement.

Robbins will then leave the civil service at the end of the fellowship to become a managing director in Goldman Sachs' Investment Banking Division.

He will join former European Commission President Jose Manuel Barroso, who is the non-executive chairman of Goldman Sachs International.